This feature is currently in public beta and available for both Cloud and self-hosted customers as well as desktop and mobile app. For more information please see our 7.0 announcement blog post: Mattermost v7.0 is now available - Mattermost
I upgraded Mattermost Team Edition to the version 7.4 recently. I could see the the call feature available but it is not working. I could start the call but after 10 seconds it stops mentioning an error as in screenshot.
this is most likely related to timeout issues or an improper reverse proxy configuration. Since this is an announcement post, please create a new issue in the troubleshooting section of this forum and provide details about your installation (method used (binary, docker), topology (reverse proxy, firewalls, loadbalancer, etc.)) and we’ll for sure find out what’s causing this issue.